Jonathan Papelbon's season is over.

The Washington Nationals announced Monday they've suspended the right-handed pitcher four games for his actions in an altercation with Nationals outfielder Bryce Harper on Sunday. Additionally, Papelbon agreed to drop the appeal of his three-game suspension from Major League Baseball for throwing at Baltimore Orioles third baseman Manny Machado last week.

"The behavior exhibited by Papelbon (on Sunday) is not acceptable," Nationals general manager Mike Rizzo said in a statement. "That is not at all in line with the way our players are expected to conduct themselves, and the Nationals organization will not tolerate it in any way."